目的 探究脉冲频率对镁锂合金黑色微弧氧化膜层的色度及其在海洋环境的耐磨性能和抗腐蚀性能的影响。方法 复合添加Cu2P2O7和CoSO4 2种着色盐，并调控脉冲频率在镁锂合金表面制备了黑色微弧氧化膜层。结果 由于脉冲频率的增加，Co元素在膜层中含量占比逐步增加、而Cu元素含量占比逐步减少，膜层由红棕色转变为黑色，黑度值最小可达24.95;频率为1 000 Hz时，摩擦因数仅为0.13，磨痕宽度为206.52 μm，耐磨性能显著提升，且腐蚀增重最少，仅为0.5 mg/cm²。阻抗提升了1个数量级。结论 调控脉冲频率可影响微弧氧化过程中的弧光放电现象，增大脉冲频率可增大膜层黑度;其结构更加致密，从而提升了膜层耐磨性能及抗腐蚀性能。

Magnesium lithium alloy is a metal structural material with excellent comprehensive performance, which has broad application prospects in fields such as shipborne aircraft. However, the poor wear and corrosion resistance of magnesium lithium alloy in marine environment greatly limits its application and promotion. In addition, the engineering application of magnesium lithium alloy also needs to meet the requirements of decoration, absorption or shielding of stray light. A black micro arc oxidation coating was prepared by adding two colored salts, copper pyrophosphate (Cu2P2O7) and cobalt sulfate (CoSO4) to the electrolyte. The resulting coating exhibited numerous defects such as microcracks. The microstructure and phase composition of the micro arc oxidation (MAO) coating were improved by adjusting the pulse frequency to enhance its wear and corrosion resistance in marine environment.